What's with the PDP Authentication Failure when connecting iPhone 4 to a cellular network?

I've bought an iPhone 4 and the text and calling work fine, as does wifi. However, when trying to use internet without Wifi I get a "Could not activate cellular data network - PDP authentication failure".

How can I fix this?


Solution 1:

There have been a lot of different attempts to fix this general error in different ways. Some of these may work for you.

  • Remove the SIM card from iPhone 3G, turn off the phone, reboot, then reinsert the sim card and wait an hour or two.

  • Go to Settings -> General -> Reset -> Reset Network Settings on your phone to reset the network setting on the iPhone.

  • Change SIM Card

  • if nothing else works, call AT&T and have them reset your number.

Solution 2:

I just got this problem fixed for Argentina calling t-mobile tech support. They were great.

Calling worked. SMS worked. Data - did not work. APN Authentication Failure

Tried before this - airplane mode - cell settings reset - power cycle (turn off/on) phone - hard reset - network setting reset - several APN profiles (only useful if you change to local SIM card)

The data roaming ON was set on my phone, but that wasn't working on movistar service. They had me dial a special code to turn that on on the network for my line.

#766#

And it turned data roaming on and instantly - data was back on.

http://support.t-mobile.com/docs/DOC-2822